Help! My geothermal system is not working properly!

Discussion in 'Maintenance and Troubleshooting' started by susanhoover, Dec 29, 2009.

  1. susanhoover

    susanhoover New Member

    I would really like some opinions on what you think is the problem with our system.

    We had a Water Furnace geothermal system installed last year-completed 8/08. It replaced our older oil furnace and air conditioner. Our oil furnace heated very well but it was very expensive.(in Jan and Feb we burned through 500 gal of oil a month.) We chose geothermal because of the reduced carbon footprint and the long term energy savings.
    The geothermal ststem has 3 zones- the living room is one zone, the kitche, dining and den the second zone, and the basement and bedrooms the third zone.

    It cooled well in the fall but our troubles began when the heat went on in late November. Our bills were sky high- $800 for electric. The company came out to check the system and determined that the outside electric temperature censor was broken so the electric over ride was always on. With this replaced, we had high bills for Dec and Jan also. The electric over ride seemed to go on any time the outside temperature was below 32 degrees.
    My husband disconnected the electric over ride so it would not go on. We were very cool inside but the cost of heating our home was too much. We did connect it for the coldest days but we have not been satisfied.
    We had the installer come back many times. He determined that we did not have enough insulation in the roof and this was why it stayed cold. We wanted to know why they did not advise us about this before we installed geothermal.
    By this time it was spring and we did not need heat. The system cooled our house great.
    Now it is winter. Once again we are having trouble. We had insulation installed to R60 and all the ducts in the attic were sealed, as well as the tops of the walls.
    The house was warm until the cold weather began. Even with the override, our bedroom and basement did not get warm.
    The installer came back and determined that the baffle for the bedrooms was not working. He has order a replacement.
    In the mean time, the bedroom zone is open and we are warm. But the upstairs bedrooms which are also on this zone are hot. Even with the electric override disconnected.
    When all the zones are at the correct temperature, the system did not shut off. We had to physically turn the system off because it was 84 degrees in the bedrooms. The outside air was in the 50's.
    Now we have really cold weather- in the 20's. The bedrooms are nice and warm, but the rest of the house is cool, it will not get above 64 degrees, and the colder it gets outside, the colder the downstairs gets.
    We are still waiting for the baffle to be replaced.

    I think that the thermostats for the living room and bedroom are not working properly. They are RF, so are not hard wired in. This may be some of the problem.
    In the winter when it is cold, the ground loop pipes are covered with frost, as is the round flow box it passes through.

    The installers have said to us that there is not enough heat in the ground for the winter because we did not run the air cool enough in the summer so the heat was not stored in the ground?? I really find this disturbing and question his abilities.

    I would really like some opinions on what you think is the problem.

    My feelings are that this system is not installed or set correctly. The company we chose is a certified Water Furnace Dealer. They have been around over 25 years and have a good reputation. We cannot understand why they can not get our system to work properly. The system cost a lot and so did the insulation. I would like to see some benefit for the money we paid.
    Last edited by a moderator: Aug 29, 2010
  2. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    Being a "dealer" does not mean

    One can size or install systems properly.

    We will need more input.

    It would be nice if the manufacturer had a commissioning or start up check list in the O/I manuals.
  3. teetech

    teetech Member Forum Leader

    Go to WF web site under dealer locator for your area and contact the Territory Manager. Request that he pay you a visit.
  4. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    Sorry to hear about your dillema. There are several red flaggs here, and we will need more info to help you narrow in on a solution.

    Request a copy of the manual J that was done.

    Request a copy of the design for your loops.

    By comparing the manual J calculations to the loop design you may find a discrepancy in the two, or a mistake was made on one or the other in regard to real life. If you placated installer by spending on insulation and the problem still exists, is a bad omen. Because your loop pipes and flowcenter are frosted, we can assume a low ewt.
    Hope this helps
  5. susanhoover

    susanhoover New Member

    What is a manual J? I am not familiar with this.

    Here is some more specific info:
    Building Area: 3803 sq ft.
    Cooling load: 62,580 Btuh
    Heating Load: 115,911 Btuh
    He has balance point set at 48
    We have 1 Geothermal Closed Loop System in a total of 2 borings.
    We have a Envision model ndv064a10, 5 ton with Arzel 3 zone air dampering system.
    Humidifier, Air Cleaner and Oxyquanton

    The part that freezes is the copper part of the ground loop connections in the geolink flow center, as well as the pipes leading from the flow center into and out of the heat pump.
  6. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    A manual J addressesthespecific heat loss and gain for your house. A five ton unit running on a total of two borings is the nextpoint of interest. How deep is each boring? What diameter is the loop piping in each bore? Were the borings made in rock?
  7. dgbair

    dgbair Just a hobby Forum Leader

    Almost seems like the zones are swapped and/or the thermostats..... Did you ever try setting the downstairs thermostat down low and the upstairs thermostat high?
  8. Palace GeoThermal

    Palace GeoThermal Well-Known Member Industry Professional Forum Leader

    The heating and cooling load are from the Manual J
  9. Palace GeoThermal

    Palace GeoThermal Well-Known Member Industry Professional Forum Leader

    A 5 ton heat pump will only give you about 50,000 Btuh at 30° EWT. Your house needs 115,911 Btuh.

    I would be asking the installer to explain how this is supposed to work.
  10. agreed-the system isn't up to the task. You will need additional geo capacity or a substantial backup system for heat-like a four ton gas furnace.
  11. susanhoover

    susanhoover New Member

    Each well is 400 ft deep.
    1.25" poly pipe
    casing top is 5' below grade
    grout used is benonite
  12. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    WOW is all I can say. For a five ton unit to be on 1600 feet of pipe is cutting it really close even with perfect conductivity. Couple that with a 10 ton load from a 5 ton machine, no wonder your electric consumption was high, with that load on aux. heat. I would be asking some really pointed questions about the math here in regard to your install.
  13. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    How old is the house, are we talking old drafty farmhouse? Those are pretty big loads. I just did a contract load calc for someone in your area (New Caste/ used Wilmington as reference town)and with 3000SF he has a 54kbtu load (winter design low is 14* F). The gain was also about 67 pct of the loss yours was closer to 50%. No smoking gun here, but it suggests a second look.
    Did the load calc you posted come from the installing contractor?
    While I agree that you should have been told first, if we find you can fix the problem by improving the envelope (insulation etc)that would be better for you than other scenarios.
    Incidently while I'm not a well driller and will yeild to pro's in that department, 1600' of 1 1/4" pipe is more than the 1500' of 3/4" that we would use in mid MI for a 5 ton.
    Good Luck,
  14. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    What is the model of your heat pump? Is it two stage?
    I have suspicions about your duct work.
  15. susanhoover

    susanhoover New Member

    I have very large duct work.
    The model is Envision Dual Capacity 064.
    Model # NDV064A10IntL
  16. Referring back to the post by palacegeo (which hit the nail on the head)-a five ton system capable of 50,000 btu is not going to handle a load of 115,000 btu heat loss without a backup heat source that can handle the difference. We sometimes use hot water coils or a gas furnace as backup on systems that have a very large disparity between heating and cooling loads because resistance heat is so expensive to run. Was the load calculated prior to adding the additional insulation? I can't understand how the system was sized as a five ton system based on the load calculation numbers. Maybe I'm missing something.
  17. susanhoover

    susanhoover New Member

    This weekend was very cold (18-20 degrees F)and very windy. The copper disc on the geolink frosted up, as did the leaving water pipe. We needed the to use the electric aux heat to keep the house warm.
    We calculated that we use $80 in heat yesterday.
    Why use geothermal if it cannot keep our house warm without aux heat?
    I am sure something is very wrong.
    What should I do? How can this be solved?
  18. urthbuoy

    urthbuoy Well-Known Member Industry Professional Forum Leader

    The summary:

    Your system is undersized. Industry standards put design loads in to 70-100% of building loads. You're at 50% of building heat load at best, given the numbers you've provided.

    You are experiencing frosting as the system is going through longer than expected run times based on its undersizing.

    Designing to 50% is not the end of the world, but you likely need a better option than electric heat to make up the difference.
  19. susanhoover

    susanhoover New Member

    I called the Terrtory Manager and they recommended that I contact another installer.
    I was hoping they could be of more help but I guess not.
  20. susanhoover

    susanhoover New Member

    They came back on the 30 and said the thermostats were switched.
    I don't know how this happened- we didn't move them.
    We marked the outside -Zone 2 and Zone 3.
    They came back again on the 7th- They said the thermostats were switched- I showed them the label, and they said that we must have removed the covers and switched them. I am frustrated and the zones still do not work.

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